Molded article and process of making the same.



UNITED STATES PATENT oEEIoE.

HENRY HICKS HURT, 01 NEW YORK, 11'. Y., ASSIGNOR TO ROBESOIN' PROCESS COMPANY,

OF NEW YORK, N. Y., A CORPORATION 01 NEW JERSEY.

1J0 Drawing.

To all whom it may coawcm:

Be it known that I, HENRY HICKS HURT, a citizen of the United States, residing at New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Molded Articles and Processes of Making the Same, of which the following is a specification.

This invention relates to molded articles and processes of making the same; and it comprises as a new article of manufacture bri uets, cores, and other shaped articles, roa surfaces, etc., made of sand or the like bonded together with a sulfite waste liquor preparation and clay and impregnated with paraflin, wax tailings or the like; and it also comprises a method. of makin such articles wherein sand or the like is ended with a waste sulfite liquor preparation, advantageousl in the presence of cla and dried and 1s thereafter impregnate with wax tailings, melted paraflin or the like all as more fully hereinafter set forth and as claimed.

A bonding agent of general use for very many purposes is now commercially made from waste sulfite liquor; and occurs on the market either in the orm of a thick liquld of about 30 Baum density or as a dry material. In the sulfite process of making pa er pulp, wood is heate under pressure wit a solution of acid sulfite of lime, or.a solution containin acid sulfites of lime and magnesia in tl ie event that dolomitic lime is used for making the original sulfite liquor. About half the wood goes into solution and about half remains behind as paper pulp or cellulose. Little is known of the chemical constitutionof the part of the wood going into solution but for the sake of a name it is often called lignone. In going into solution the li one unites with the acid sulfite to form sa ts of new complex acids derived from the lignone and containing sulfur. These acids are united to the bases of the original sulfite li uor. Nothing is known de 'tely as to t e constitution pf these Specification of Letters Patent.

Application Med December 6, 1916. Serial No. 185,155.

complex acids, but, again for convenience in nomenclature, they are called lignosulfonic acids and the salts lignosulfonates. As the sulfite liquor comes from the digester it is a thin watery liquid containinlg the stated bodies. It is of quite unstable character but by proper precautions, including careful neutralization and evaporation in cacao (Patent 833,634) it may be concentrated to stable, thick liquids or to a dry preparation. Both are on the market. It 1s material of this character which I most advanta eously use in the present invention althoug other preparations may be em 10 ed; as for instance, pre paratlons ma e y evaporating the liquor 111 an acid condition.

As stated, little is known of the chemical nature of thlsmaterial other than it contains constituents of the wood, sulfur and the bases of the original sulfite liquor. It is highly colloid in its character and is possesse of good binding properties. A large part of its use commerclally is for bonding purposes and it is extensively em loyed for making sand cores, briquets an the like. It is also largely used 1n surfacin roads. The lignosulfonates are all soluble 1n water and articlesmade of sand bonded withthese preparations, such as sand cores, as a rule are not resistant to moisture or steam. The sameis true of briquets and bodies made of most other granular materials as for instance coal. Nevertheless the sulfite liquor preparation finds an extensive use in makmg sand cores and many other articles. For some reason which is not known it has been found that in making briquets and cores from sandand many other materials an addition of clay to the sulfite waste fliquor gives a stronger bonding action; the bondmg action being greater than the sum of the bonding action of the sulfite liquor alone, and that of the clay. alone (see Patent 1,069,031). The clay also adds to the water resistant qualities of the bonded article. Why these actions should take place is not known since there is. no obvious chemical reason for the same. This fact however contributes materially in making the sulfite liquor preparations useful in bonding or surfacing roads; an application in which they now find a large use (see Patent 1,069,029).

I have found that in makin briquets and cores with sand bonded by c a and waste sulfite liquor preparations that can obtain a great increase in stren th for some reason by impregnating the article after its manufacture and drying with wax tailings or other form of paraffin. Wax tailings are the crude material from which parafiin is commercially made. In distilling petroleum, after the lighter fractions are distilled over it is the custom to push the distillation with the aid' of steam. The last distillate going over before the residue in the still is converted into coke is what is known as wax tailings. In and of themselves parafiin and wax tailings have no substantial binding action for the present purposes; nor do they give shaped articles of any degree of strength. They have a waterproofing action of course but no strengthening action ord1 naril But I have found that for some reason t ere is a great increment of strength in treating these molded articles made as described with paraflin of wax tailings. The same principle ma beapplied in surfacin roads of sand or t e like. In such event, preliminarily impregnate the surface of the road with a sulfite waste liquor preparation, which ma be either the described commercial 30 aum concentrate rediluted to a convenient strength or may be a commercial dried preparation dissolved in water. After a period of time to allow the road to dry somewhat it is next impregnated with hot wax tailings, or with wax tailings diluted down with a lighter oil. The liquid sulfite preparation may be mixed with more or less clay prior to application to the road. Very frequently however there is enough cla even in a sand road to make a s ecial a mixture of clay with the sulfite iquor unnecessary.

In one specific instance in making cores under the present invention, certain cores were made with commercial 30 Baum sulfite liquor, clay and sand, clay and sand being used in the ratio of 15:85 and the sulfite liquor in the proportion of one part by volume of the commercial 30 Baume liquor to 25 parts by volume of the sand clay mixture. These cores on drying gave a tensile strength of about 230 pounds per inch. After manufacture and thorough dr ing the cores were dipped in melted para n and, stren e'ly enough, the tensile strength was foun to increase about 40 per cent, the cores now showing a stren h of 322 pounds. Similar results were obtalned with the use of wax tailings in lieu of paraflin. The

dipped articles were of course thoroughl waterproof, the wax having a waterproo ing function in addition to 1ts function as a co-binder with the sulfite liquor.

I find that the preparation of the core or briquet and drying should be'preliminary to the use of the wax or wax tailings to obtain the results here noted. When the wax or wax tailings is emulsified with the sulfite li uor the result is not so good.

hile I have described this invention more particularly in its use for bonding sand cores and the like it is of course not restricted thereto but may be applied; to cores and bricks made of other granular materlal, such as pyrites fines, coal and the like; and to making roads and a wide variety of other urposes.

While I ave described this invention more particularly as a plying to the production of molded artic es wherein the bonding agent contains both a waste sulfite liquor preparation and clay, I find that waste sulfite liquor alone may be used for bonding and the dried article afterward impregnated with or dipped into a melted parafiin or wax tailings with an increase in the strength of the articles as compared with the same article not so dipped or impregnated and this strength it retains because of the waterproofing action of the wax. Various other admixtures with the sulfite liqp or other than clay may of course be used.

he wax tailings may of course be more or less admixed with other oily materials for venous purposes. I find the wax tailings however suflicient for most purposes, though for special applications I may 111001- porate linseed oil, petroleum oil, etc.

What I claim is: 105

1. An article composed of ranular material bonded and united by a onding agent comprising clay and a waste sulfite liquor preparation, sald artlcle being impregnated wit a waxy material.

0 2. An article composed of ranular material bonded and united by a onding agent -comprising a waste sulfite liquor reparation, said article being impregnate with a waxy material.

3. An article composed of ranular material bonded and united by a onding agent comprlsmg clay and a waste sulfite liquor pre aratlon, sald article being impregnated wit wax tailings.

4. An artlclecomposed of anular material bonded and united by a onding agent compris ng a waste sulfite liquor preparation, said article being impregnated with wax tailings.

5 The process of making bonded articles whlch comprises bonding granular material Wltll a bohdmg agent comprising clay and waste sulfite liquor, drying and impregnatmg with a waxy material.

which comprises bonding granular material waxy materi with a bonding agent comprising clay and In testimony whereof, I aflix my signawaste sulfite liquor, drying and impregnatture.

6. The prooess of making bonded articies fite liquor, dilyling and impregnatin with a 5 ing with wax taiiings. HENRY HICKS HURT.

The process of making bonded articles Witnesses: which comprises bonding granular material B W. BnLmJN,

with a bonding agent comprising waste sul- J is. A. SHIRRAS. 

